Catherine Deneuve's new film On My Way is the latest in a prolific career

Catherine Deneuve may be the grande dame of French cinema, but the 70-year-old - be it out of modesty or pure awkwardness - still gasps when she is reminded of her status as one of the great beauties in film history. "That is …" she pauses for a giggle. "That is another story."

The actress, in town for a screening of her latest film, On My Way, at the 38th Hong Kong International Film Festival, is perhaps a little fatigued from her dinner commitment the previous night - to celebrate the 50th anniversary of Sino-French diplomatic relations - when we sit down for an interview in a spacious suite high up in The Peninsula hotel last Monday.

We miss people like Truffaut or Buñuel or Demy, of course … But I think that there are very interesting directors [today]

catherine deneuve

But while she is in no mood to pose for a portrait shoot, Deneuve, hiding behind a pair of sunglasses that only partly conceal her eyes, is happy to engage in some nerdy film talk. The only time she sounds slightly wistful during our conversation is when the topic of "ageing beauty", the subject of her new film, is brought up.

Written and directed by Emmanuelle Bercot, On My Way is a soul-searching road movie in which Deneuve, who appears in almost every scene, plays a former beauty queen whose life has reached an impasse. The film had its world premiere at last year's Berlin International Film Festival.

"You have to live with it, you know," she says. "It's like [when you're] getting older, it's a little more difficult for an actress than for a normal person, I suppose. But it's not a major concern, frankly. There are so many more interests you have in life, that you don't see things the same way like when you started your career, when you're 30. It's very different."

In a way, it's a testament to her lasting sex appeal that Deneuve finds herself falling in bed not once, but twice in the film. Does it help that a female director is at the helm of this intimate character study? "Certainly, yes," she says. "I worked with different woman directors, [like] Tonie Marshall, Agnès Varda [and] Nadine Trintignant. I suppose women have a different approach to the psychology [of the characters]."

Indeed, Deneuve has developed such a rapport with Bercot that they have already decided on their next collaboration, which starts shooting this summer: Deneuve will play a judge in a story about a young delinquent. "I like her very much," she says of the director. "We get along very well when we speak about the film or when we're shooting. I feel very involved in the film with her."

Fruitful working relations with revered filmmakers have defined Deneuve's career. Her list of collaborators makes for a staggering who's who of cinema's all-time greats: she has made at least two films each with Jacques Demy, Luis Buñuel, Varda, François Truffaut, Arnaud Desplechin and François Ozon; and six with André Téchiné.

Born Catherine Dorléac in 1943 to actor parents, Deneuve took her mother's maiden name at the start of her career to avoid clashing with her older sister Françoise, who co-starred with her in Demy's The Young Girls of Rochefort (1967). Françoise died in a car accident the same year.

After rising to fame with the 1964 musical The Umbrellas of Cherbourg ("I wasn't really sure that I was so interested in being an actress"), Deneuve staked her claim as the ice queen of cinema with her early collaborations with Roman Polanski ( Repulsion) and Buñuel ( Belle de Jour, Tristana).

Famously dressed by Yves Saint Laurent in several films (including the steamy vampire drama The Hunger in 1983), Deneuve, who was a longtime muse of the designer, became a symbol of chic with her housewife-turned-prostitute character in the sadomasochistic masterpiece Belle de Jour (1967).

She cemented her status as one of the most important actors of her generation with her first César Award-winning role in Truffaut's The Last Metro, opposite Gérard Depardieu. "It was a sort of turning point," she says of the 1980 film. "Truffaut wrote this part for me because he wanted me to play a woman with responsibilities. You know, because with cinema there are a lot of - how do you say it? - archetypes of women. It's true that it's not often you have a part with strong responsibilities in life."

It is because of these audacious artistic choices that Deneuve is sometimes credited with having the eye of a cinematic auteur. But she is not interested in directing. "I know Arnaud Desplechin said I was my own director. When you look at the choices] in my career, I was more like a director for myself but I don't have any intention of directing. It's really very, very special to direct a film. It means having to make decisions all the time. I don't feel like I could fulfil that."

Having worked with so many influential filmmakers over the past five decades, Deneuve says she doesn't buy into the notion that the glory days of cinema are gone. "I think we miss people like Truffaut or Buñuel or Demy, of course … But I think that there are very interesting directors [today]." She pauses, then says: "I don't know if you've seen the films of Jacques Audiard. You know him? The French director?" Before I have the chance to even nod, Deneuve interrupts herself. "But it's not the same. It's not like Truffaut or …" She seems to go over a checklist in her mind and finally says: "But Polanski is still there."

Could we explain the perceived dearth of iconic auteurs today as a result of the fading popularity of the "auteur theory", the influential approach to film criticism advocated by Truffaut that made legends out of Akira Kurosawa, Satyajit Ray and Alfred Hitchcock?

"In fact, we still have directors who are writing their scripts," Deneuve says. "I remember when I did a film like Le Sauvage (1975) by Jean-Paul Rappeneau, you could see sometimes there were three names [credited] on the script, for dialogue and [the scenario]. That has changed today: a lot of good scriptwriters want to make films - and when they are good, nowadays they make their own films."

She adds with a grin: "There are too many films being made in France anyway." Then a bigger smile. "Too many, oh yeah."

Not that Deneuve is complaining - especially not when she attributes her career longevity to her passion as a movie-goer herself. "I've always been interested in films. I go to see a lot of films. I watch all kinds of movies. I suppose my way of reading scripts is different [from others] because I don't always think of only my part or what I could be in the film; I see the film as an entity that I want to be involved with."

She names Hirokazu Koreeda's Like Father, Like Son, Kiyoshi Kurosawa's miniseries Penance and Alain Guiraudie's Stranger by the Lake as recent favourites. So I ask Deneuve, who won her second best actress César for her part in the Vietnam-set epic Indochine (1992), if she's interested in working in Asia again. "I'd love to, but I don't see why I would come to work here unless there [is] a film with a part for a European actress," she says. "I think also Asian directors would go probably more towards English or American actresses because of the language. But I'd love to, yes. I love Asian cinema."

With a steady output of at least one film per year, there may well be yet another chance for the actress to revisit this part of the world and add to the 110-plus films in her oeuvre. In any case, Deneuve is determined to keep working until her passion dries up - which looks unlikely at the moment.

"I do film because I like it very much," she says. "And if I start to get bored or think that the parts are not so interesting anymore, I don't think I will go on."